Adds StemTremolo to the note column's element list.

Adds StemTremolo to the note column's element list.

[MikeSol, 2011-09-19 05:45:04]

Hey all,

While working on flags, I noticed that horizontal spacing changes when a grob is
part of a NoteColumn's element list.

I went back to StemTremolos and tested this out: run the code below with and
without this patch:

\relative c'' {
  \time 8/4
  \autoBeamOff
  \override NoteHead #'stencil = #(ly:make-stencil '() '(0 . 0) '(0 . 0))
  \override Score . PaperColumn #'stencil = #ly:paper-column::print
  \repeat unfold 8 { b4:32 }
}

You'll see that StemTremolos, when part of note columns, lead to more space.

I'm still not sure why this is the case, but it seems that all things that
"look" like they're part of the note column should work similarly in the
spacing.

Cheers,
MS

[Neil Puttock, 2011-09-19 17:02:42]

On 2011/09/19 05:45:04, MikeSol wrote:

> While working on flags, I noticed that horizontal spacing changes when a grob
is
> part of a NoteColumn's element list.
> 
> I went back to StemTremolos and tested this out: run the code below with and
> without this patch:

I'm getting deja vu here Mike.  Wasn't this your original idea for fixing the
collisions with tremolos?

Are you saying we need both the pure-height function *and* the addition of
StemTremolo to NoteColumn's elements array?

Cheers,
Neil

[mike_apollinemike.com, 2011-09-19 18:48:17]

On Sep 19, 2011, at 7:02 PM, n.puttock@gmail.com wrote:

> On 2011/09/19 05:45:04, MikeSol wrote:
> 
>> While working on flags, I noticed that horizontal spacing changes when
> a grob is
>> part of a NoteColumn's element list.
> 
>> I went back to StemTremolos and tested this out: run the code below
> with and
>> without this patch:
> 
> I'm getting deja vu here Mike.  Wasn't this your original idea for
> fixing the collisions with tremolos?
> 

Indeed, but it was my idea only because I had no clue what I was doing.  I still
have no clue what I'm doing, but I have a better sense how to frame that about
which I have no clue.

> Are you saying we need both the pure-height function *and* the addition
> of StemTremolo to NoteColumn's elements array?
> 

Yup.  Or rather not that we "need" this, but that:

(a) StemTremolos in the element array result in different visual output from
their not being part of the element array; and
(b) Given that the stem, arpeggio, and flag are part of the element array, it
seems that the StemTremolo "belongs" to this family and should thus have the
same impact on spacing (meaning it should belong to the array).

What I'd really like to know is why the spring ideal and minimum distances are
different just by virtue of its belonging to the array, but I have a feeling the
answer lies deep in the bowels of the horizontal spacing code and I don't have
time to get to the bottom of that in the foreseeable future.  For now, it seems
like this is the right move to take.

Cheers,
MS

[pkx166h, 2011-09-24 19:14:53]

passes make, get some reg tests show up but nothing of note.

See attached on

http://code.google.com/p/lilypond/issues/detail?id=1922#c1

[Keith, 2011-09-25 05:38:54]

On 2011/09/19 18:48:17, mike_apollinemike.com wrote:

> What I'd really like to know is why the spring ideal and minimum distances are
> different just by virtue of its belonging to the array, but I have a feeling
the
> answer lies deep in the bowels of the horizontal spacing code and I don't have
> time to get to the bottom of that in the foreseeable future.  

I doubt anyone can remember this faster than you can figure it out.

Note_spacing::get_spacing() uses the horizontal skylines of the NoteColumns to
set the spring lengths.

Spacing_interface::skylines() sets these skylines using the elements... somehow.
 Probably the elements' extents are the boxes over which the skyline is draped
(or rather, shrink-wrapped since it is the skyline for horizontal spacing).

[Neil Puttock, 2011-09-25 14:33:16]

On 19 September 2011 19:48, mike@apollinemike.com <mike@apollinemike.com> wrote:

> What I'd really like to know is why the spring ideal and minimum distances are
different just by virtue of its belonging to the array, but I have a feeling the
answer lies deep in the bowels of the horizontal spacing code and I don't have
time to get to the bottom of that in the foreseeable future.  For now, it seems
like this is the right move to take.

I'm afraid I disagree.  Looking at the changes James has posted on the
tracker, we now get undesirable extra space in some beamed tremolos,
which looks strange.  They shouldn't influence the spacing unless
absolutely necessary.

Cheers,
Neil

[mike_apollinemike.com, 2011-09-25 18:18:59]

On Sep 25, 2011, at 4:33 PM, Neil Puttock wrote:

> On 19 September 2011 19:48, mike@apollinemike.com <mike@apollinemike.com>
wrote:
> 
>> What I'd really like to know is why the spring ideal and minimum distances
are different just by virtue of its belonging to the array, but I have a feeling
the answer lies deep in the bowels of the horizontal spacing code and I don't
have time to get to the bottom of that in the foreseeable future.  For now, it
seems like this is the right move to take.
> 
> I'm afraid I disagree.  Looking at the changes James has posted on the
> tracker, we now get undesirable extra space in some beamed tremolos,
> which looks strange.  They shouldn't influence the spacing unless
> absolutely necessary.
> 
> Cheers,
> Neil
> 

Ok - I'll try a different approach next week.

Cheers,
MS